Roof scraper



Aug. 1o, 1943. F, N. BARE [2,326,514

ROOF SCRAPER Filed Feb. 1'7, 1941 2 Sheets-Sheet 1 digi Aug- 10,1943- F. N. BAR@ I 2,3%,514

` ROOF SCRAPER Filed Feb, 17, 1.941 y 2-SheetS-Sheet 2 Patentet'lAug. 10, 1.943 'f i Yinvention'relates to 'a rodi scraper afde- `viceffor removing'old accumulations ofgraveland lbinerferr-roofs preparatory torresufaoing.

ily vportable -easily handlabie 'power "scraping 'apf- Yparatus 'of "ai lilrdvvlii'ch imay V'befrea'dily "used 'on 'smaller roofs; another `ieatureof this linvention is the provision of improved mounting meahsfor supporting a *Working'assembly' comprising a scraping tool, "a motor'Tor driving 'ftheivtdolfand vhandi'es for 4-the'u'se-of ithe operator; -yetandtn-er 'feature of this invention is the fac't'tthatit'i'is''so .arranged thatfthieto l'does notlnadvertently'cit Ainto the 'basema'terial'wet thgarrangm nt s Y K15 ing' or asphalt or bitumen'and fa :wear-resistant surfacingof sma11-`stone`orgray1. In 'laying new roof itis desirable"to.scrapeoithis 'gravel and some o'f theasphaltpinder, but Without damaging the felt or similar base material.

. It has `been generally customary to do this scraping of the old roof surface byV hand. There have heretofore been available large rotary machines, but these have been of such a size and Y weight as to prohibit their use on any but the largest roofs. There has also been at least one attempt heretofore to use lighter power motors CII.

viceY could be' 1used in 'sfof'far as myl'prefsent 'irivenjA for operating the scraping tool, reference being had to the structure shown in Miller Patent 2,197,154. This has several defects and objections, however, Which my present invention obviates. I provide a considerably inclined scraping tool and driving motor, together with handles enabling the Workman to properly control the depth of cut, these handles being adjustable to the best position for a given worker. Working assembly on a carriage, and employed I have mounted the l counterweights, the arrangement beingsuch that a two-wheel carriage supports the apparatus near its point of balance.

I have found it preferable to unbalance `the apparatus slightly to the rear, so that'some up-v ward force 0r lift on the handles is necessary to bring the tool into working position.

In the particular embodiment' of my invention I .illusiratedhrewih the .Scrapingteielzl n is a type :provided 'vvithatvvide blade'and a ishankfof Such shape vand size that it Yiraayjloe ccnvemehuygreceived jloyv the vlovver Yend fofj conventionalfpercfusl Vdesiredlv impacts to" the tool I employ; in 'this :ein-

bodiment, an ii'iternaly combustionv percussve hammer 'of Ythe free piston type, thisj being here indicated in "g'eneral as II. 'In this form .ofjperf 1 :l

cussive device `gasoline from; the tank I 2 is mixed with air andj' the explosive'jmixtlile' ydelivered to Va ,space in the cylinder (L3 .bjeneath vthe 'piston 'freely `reciprocable therein the 'resultant explosion'V driving the piston down to deliveritsjfworling impact through 'anganvilfto 'the scraping ftoolj III, Internal co'mbu'stionper cussivedevicesfoffthis typejare being marketed 'byfme and areWell knownin'gthe trade,t and I Will therefore notl ydescribe it 'infurthe'rfdetaiL Refer-l ence maybe'had vto such patents asV Charles Pfat-v ent 2,180,034 and Boddingnouse Patent '2,162,416 for further specific information. Except that'an internal combustion' hammer isfparticularly sate@ Y isiac'tory from the standpoint of portability, any

otherfform of conventional percussivefmotorfd tionis'concerned;'

Handle means for manipulating the deviceare here shown in the form ofvrearwardly extending slightly divergent rodlike members I4 and' I5.l These maybe of any convenient material, it being vfound preferable to vmake them of'holl'ow piping to save Weight, and to reinforcethem by appropriate ribs I6 and II 'wherethey join the mount-` ing plates I8 and I9. 1These`mounting plates are. adjustably attached toa yoke atthe top of .the percussive hammer, this being here Vshown as conveniently accomplished by bolts passed' through slots in the associated parts.' As is readily ap`A ,Y parent, the adjustment is a rotative one enabling theV outer ends of the handles'to .be raisedoi'. VV lowered With respect tothe percussive motor by."Y

loosening 'the bolts,Y moving` the'handles to the desired position, and then drawingup the bolts.

The range of adjustment is, ofI course, limitedby Vthelengthof the slots. l v l 1 Supporting means for carrying the' Workingv assembly is here shown inthe form of a frame 20 having a cross piece on which the percussive motor is rigidly mounted, and sidepieces between Vwhich lthefwh'eels 2I and k22 are mounted. The side pieces, as the piece-23,' extend forward of 1 the Wheels and carry, attheir outerends,y couny kAtjan appropriateV 'time thiS'is transferred tothe firing .space above the piston, and there ignited .b an electric spark;

terweights 24 and 25. While these' counterweights are here shown in the form of solid cast metal wheels, they have no function as Wheels, and are rigidly mounted. The arrangement is such that the axis of the wheels 2| and 22 substantially intersects the axis of the scraping tool and the cylinder of its operative motor, being somewhat forward of the center of balance of the Working assembly, as counterweighted;

That is, when the device :is inoperative the Whole thing pivots for .rotates about the axis of the wheels 2| and 22 until the back end of the carria-ge, or some other part of the device, comes into contact with the surface being scraped." That is, some upward force on the handles is necessary to bring the tool into `the working po. sition shown in the accompanying gures. I

have so arranged the balance of the apparatus;

that a force of ten or fteen pounds on the handles is sufficient to bring the tool I into engagement with vthe roof or similar surface being` scraped. .The fact that the axisof' pivotalmounting is near the centerv rof balanceofthfe apparatus preventsrundu'e fatigue on the Workman; yet the pivotalrnounting enablesvery good control .of the depth Vof cut desired. In operation a workman grasps the Vtransverse handles 26 and 21 fat the back end. of the members I4 and vI and lifts upwardly untilthe working vend of the tool I0 isin engagement with .the roof. He then exerts a little more upwardforce to. cause the tool to bite into the rroof surface, andat the same time leans or pushes forwardly. The rela- `tiveproportion of these forces, ,ofcourse, deterf vmines the Vdepth of cut ofthe tool,.sothat the material .being scraped off may be,regu1ated in ans,1 desired manner. I haveffound that, Where both upward and forward forces are to be ape pliedpthe transverse handle members are more comfortable and lessiatiguing to theY operator.v

I have Valso `provided a thrust or pusher member 28 hetween'the handle members I4 and I5. This islpreferably a metal cylinder threeor four inches in diameter, `cove'redwith a layer. of rubber. It provides a good surface against which the Workman can lean Withhis thighs'to provide forward force without` undue fatigue.v

' I have found that it is desirable to use a straight scraping tool, but of such ak kind VVthat .the'tool I0 and the operating motor I I are disposedrat this angle.

`may' be changed slightly to meet varying con- `ditions I provide a second set of openings, as 29,'in" the side members carrying the wheels. Thatwis,f the axles of the wheels 2| and 22 are In order that this angle shown'n the drawings in an opening in the side .members of the carriage substantially at the center of such side members. Whenfit is desired toincreasefthefangle 4of attack of lthe 4toolby a degree orstvvfxfii;Y is onlynecessary to move these angles to other holes provided in 'thesidemembers, as .the mounting'lhole 29; Obviously, Vas many of these may be provided as mayseemdesirable to give an approlciriate range .of adjust ment,' Vif..

While I have. shownV and'described certain Yenibodiments of my invention, Yit is tofbe .understood that 'it is capable'of 'ma'ny` modifications.

changes, therefore, inf the ,eonstrucuonan arV- rangement maylbemade without departingfrom in theappended claims.V

I'clalxrifVV 1.` Apparatus of ythe character described; including: a Workingassembly includingan inclined impact tool, a'lm'otorffor opeat-ingthe tool, and handle means; .'a supporting :arriage providing afpivotal mounting for the .Working assembly;

. the spirit and scopeof the'inventin as'disclosed and means for adjustingnthe .point of pivotal mounting.' e Y..

2. Apparatus of the character claimed in claim 1, wherein Ythe pivotalemounting" ishaboutxA the axis of apair of v,wheels of the calriage,- and wherein provision is made for -varyin g the mounte ing of the Wheels on the carriage. f Y j '4 FRANQIS N. BARD. 

